Drill



H. BERNAY.

DRILL.

APPLICATION FILED APR.5.1920.

Patented July 12, 1921.

2 SHEETS-SHEET M u 1 a I 1. .fl j y 6 1. U, fl %//%///////MZ H. BERNAY.

DRILL.

APPLICATION FILED APR-5,1920.

1,384,297, Patented July 12, 1921.

2 SHEETS-SHEET 2- zen of the United States,

' Improvement in Drills,

1 much handling,

HENRI BERNAY, (EFF SAN FEiLWCISC-U, CALIFORNIA, ASSIGNOR T0 FRED W1 THURSTUN',

91F SAN FRANGIS C0, UALIFUJRNIA.

paint.

Specification of To all whom it may concern.

Be it known that I, HENRI BERNAY, a citiresiding in the of San Francisco, State of invented a new and useful of which the followcity and county California, have in is a specification. v yinvention relates to improvements in a drill for rock boring and the like wherein reversible bits having cutting edges of dif-. ferent lengths operate in conjunction with retaining means for easily and readily renewing the utility of the drill after one set of cutting edges has become dulled through usage.

'In the present state of the art cross bits are used for drilling in which abar of steel, cross-shaped in section is enlarged by swaging at one end to provide meansfor cuttin or boring a hole of greater diameter than the stock of the drill.

After the diameter of the cutting or boring portion of the drill has been decreased hrough usage, in the case of mining, the drills are brought to the surface and re sharpened, the entire operation requiring transportation and loss of material through removing a portion of the end of the drill which may have become crystallized to such an extent that it is no longer suitable for boring purposes.

In drilling or boring holes with such 7 drills it is the practice to employ successively drills of decreasing diameter, beginning with the largest size and gradually decreasing the size of the operative or cutting portion of the drills to reduce the diameterof the hole until the desired depth has been obtained. This method is practised to prevent successive drills from binding within the holes made by previously used drills. Itis evident that after a drill has been in use for a time the wearing thereof decreases the diameter of the drill as well as of the hole drill of the same diameter is next inserted it is obvious that said new drill of full size couldnot enter that portion of the hole drilled by the former drill when slightly dulled. 1

propose to provide a new and improved drill having improved means for renewin the bits or cutting edges of the drill, said Letters Patent.

1920. Serial No. 371,741.

bits being of such a size that a quantity of the same may be easily and readily transported and as easily and readily mounted within the drill, thus greatly lessening the cost of handling and operating the drill.

having one than the other whereby and the originally or from other causes. k

A still further object of the present ina greater distance inoperatively posiof the said inoperative cutting edges to prevent binding, of said'cuttin edges in a hole previously bored by said inoperative cuttin edges.

still further object of the invention is to provide hits, the cutting edges of which are formed at the line of conver ency of beveled or chamfered faces of dif erent area, the outer chamfered or edge, when the position, the inner bevel whereb to the cutting edges and parallel to the axis of the stock will tend to move said cutting edges toward each other and thereby prevent a pressure in a direction which will tend to fracture that portion of the stock beyond the slots which hold the bits.

Still further objects of the invention are to provide improved means for retainin the bits in operative positions Wit/hill: the t e in stock of a drill and for facilitatin sertion and the removal of the blts from the stock.

I accomplish these several features by means of the improved device disclosed in the drawings forming a part of the present specification wherein like characters of refer- Patented July12, 1921;

ence are used to designate similar parts throughout the said specification and drawin s, and in which igure 1 is an elevation of my improved bit;

' of my invention;

Fig. 7 is a, vertical sectional view of Fig. 6;

Fig. 8 is a bottom plan view of Fig. 6;

and

Fig. 9 is a plan view of one of the rings used in my improved drill, the position of the bits own in Figs. 6, 7 and 8 beingindicated by dottedlines.

In Figs. 1 mb in the drawings the numeral 1 designates a tapered stock having two annular grooves or seats 2, which arev formed around one end of the stock by means of 'an annular flange 8 and an annular shoulder 4, arranged at a short distance from the flange 3, and by an annular edge 7, and the annular seats between the bevel-edged en mounted double-edged 5 located approximately midway between the shoulder and the flange. The shoulder 4 is of such a diameter that a pair .of open rings 6, each made of suitable spring material and being most clearly shown in Fig. 9, may be easily sprung over the shoulder and be rotatably seated in their respectiveannular seats 2. While each ring (Sis thus seated, there will be a gap, as shown at 8, ds 7 of the rin the purpose of the gap, the bevel-edged en s 2 being more clearly explained hereinafter.

The stock 1 is bored centrally as at 9 for the passage of water'to be used in flushing out drilled holes, an enlarged tapered portion 10 for the rece tion of a second hollow stock 11. 7

he stock 1 is alsov provided with arcuate slots 12, arranged at opposite angles and on opposite sides-of the axis of the stock 1, and within the slots 12 are removably bits 14.

Each bit 14 is provided with beveled or chamfered faces 16 and 17 which at the lines of convergency form the cutting edges of the bit, the outermost each case being of greater area than the 1 face 16, so that, when pressure is applied to the operative cutting edges,

stock.

elevation of one of ter, and,

said central bore 9 having,

beveled surface 17 in the axis of the stock and toward that part of of the stock on the sides of the slots 12 011-- posite to the aforementioned part of the One of the cutting longer than the other cutting edge of the bit, the longer cutting edge being used before the shorter edge so-that, when the originally longer edge has become dull through usa reversed, and the originally shorter edge, being then the longer edge, may be used for continuing liability of binding in the hole produced by the originally longer edge.

1n drilling holes in mining or other purposes, the present practice is to begin with a drill of larger diameas said drill is dulled, to introduce successively, drills of shorter diameter, in

order to avoid the binding of a drill within the gradually decreasing hole.

In the present invention by the inclination edges or each bit is the drilling operation without.

rocks. for blasting,

ge and shortened until it is shorter than the originally'shorter edge, the bit can beof the bits 14, within the slots 12 of the stock 1, the ends of the operatively positioned cutting edges are projected farther from the axis of the stock 1 than the ends of the'inoperatively positioned cutting edges of the bits. In other words, the distance between the diametrically opposed ends of the operatively positioned cutting edges is greater than the distance between the diametrically opposed ends of the inoperatively I positioned cutting edges. Therefore, the last mentioned edges will neither bind in a holethat'is being drilled by the operative edges, nor will the inoperatively positione cutting edges bind in a hole previously drilled by the operative edges when the 1noperative edges are reversed in order to take the place of the formerly In order to increase bits the ends thereof cgmprise fiat surfaces 18, and in each end, approximately midway therepf, is a transverse recess 21 engaged by the rings 6, which, fitting snugly, although resiliently, around the operative edges.

bits, make it impossible for the bits to movelongitudinally or laterally within their respective slots. The

bits are thus positively retained in their respective places upon the stock 1 and cannot become disengaged therefrom except by proper manipulation.

Each ring 6 is so made that the gap 8, appearing between the bevel-edged ends 7 of the ring when the ring has been sprung the strength of the over the shoulder 4 and been fixed upon its respective annular seat 2, is slightly less than the thickness of the bits 14, so that, if by the remotest possibility it should occur. during the operation of the drill that both spread the gap .7

rings 6 have been shifted longitudinally in their seats until both gaps 8 coincide with one of the ends of the slots 12, th still prevent the accidental exit coinciding with th thus retained in operative positions, a satisfactory operation sured.

To remove a bit,

coincidence with one of the ends of one of e rings will gaps 8 the bit 14 in the respective slot 12 maybe easily and readily removed longitudinally.

en inserting a bit, the chamfered or beveled cuttingedge thereof may be used to and thereby facilitate the entrance of said bit into its slot. After the b ts have been fixed in their slots, the rings b are simply moved so that the gaps 8 are out of almement with the slots and, preferably, each other" in erative posit ons. lgs. 6, 7 and 8, illustrating a modified he stock 1. is provided annular groove or seat 23, formed the flange 24 and the annular shoulder 25 and being adapted to of the previously described rings 6. It is, of course, "imderstood that the groove 23 and shape as to reseat therein two or more rings 6. he rlng 6 while seated in the groove 23 will have therein the gap 8, t which h been explained.

d intersecting each other axially of have removably bits 31, twoof which are arranged ineach slot and of the axis of the stock, and

clearly shown in Fig. 7, each bit from the side, has th 0 a four-sided figure inwhich the sides as is most blt, converge inwardl toward the axis of the stock, so that the innermost of the long sides extends inwardly f side of the stock and approximately in alinement with the periphery of the central bore 2 to a point adjacent to the axis of the stock,

for positively re,-

receive therein one th he purpose of th ner understood on opposite sides (1 cutting ed tightly in the groove 23, while at the same time on aging the recesses "35, thusv JOlIlll'lg blts, and thereby holding the bits securely within the stock. The bits thus being placed in position, it is seen that all the outer narrow sides attheir junction with the inoperatively positioned ends of the bits, us assuring free and easy cutting of the bits during the operation of the drill. hen the cuter narrow sides at the junction with the operative ends of the bits are worn, the ring 6 may be removed in a man from th gard to Figs. 1 to 4, so that then be reversed, whereafter the formerly Having thus described my invention, wh at claim as new and desire to secure by Letters Patent is 1. A drill comprising a stock having oppositely inclined slots herein on opposite sides of the axis of said w by a pressure applied to the cutting of said bits will d to move said edges toward the axis of the stock.- comprising a stock ha ing oppositely inclined slots th he axis of rotatably mounted upon the I5 positely inclined .positely inclined slots a pressure applied to the cutting edges of said bits will tend to move said cutting edges toward the axis of the stock; and means for retaining the bits within the slots.

3. A drill comprising a stock having oppositely inclined slots therein on opposite sides of the axis of bits removably mounted within the slots, the outer beveled surfaces than the inner beveled surfaces whereby a pressure applied to the cutting edges of said bits will tend to move said cutting edges toward the axis of the stock; and a ring stock to retain the bits within the stock, said ring having a gap therein of lesser width ness of the bits. 7 I

4. A drill comprising a stock having oppositely inclined slots therein on opposite sides of the axis of said stock; bevel-edged bits removably mounted within the slots, the outer beveled surfaces being of greater area than the inner beveled surfaces, whereby a pressure applied to the cutting edges of said bits will tend to move said cutting edges toward the axis of the stock; a ring rotatably mounted upon the stock to retain the bits within the stock, said ring having a gap therein of lesser width than the thickness of the bits; and the ends of the ring being bevel-edged in order to faciligate the insertion and the removal of the its. 5. A drill comprising a stock having optherein on opposite sides of the axis of said'stock; bevel-edged bits removably mounted within the slots, the outer beveled surfaces bein of greater area than the inner beveled sur aces, whereby a pressure applied to the cutting edges of said bits will tend to move said cutting edges toward the axis of the stock; and a pluralit of rings rotatably mounted upon the stoc to retain the bits within the stock, each of the rings having a gap therein 0 lesser width than the thickness of the bits.

6. A drill comprising a stock having opslots therein on opposite sides of the axis of said stock; bevel-edged bits removably mounted within the slots,

' the outer beveled surfaces being of greater area than the inner beveled surfaces whereby a pressure applied to the cutting edges of said bits will tend to move said cutting edges toward the axis of the stock; a plurality of rings rotatably mounted upon the stock to retain the bits within the stock,

each ofthe rings having a gap therein of lesser width than the thickness of the bits; and the ends of each ring being bevel-edged in order to facilitate the insertion and the removal of the bits. v

7. A'drill comprising a stock having arcuate, oppositely inclined slots on opposite bits removably aid stock; bevel-edged being of greater area' than the thick sides of the axis of said stock; and arcuate mounted within the slots and having double-beveled .cuttin edges, the

outer beveled surfaces being 0 greater area than the inner beveled surfaces whereby a pressure applied to the operatively positioned edges will tend to move said edges toward the axis of the stock.

8. A drill comprising a stock having arcuate, oppositely incllned slots on oppos te sides of the axis of said stock; arcuate bits removably mounted within the slots and having double-beveled cuttin outer beveled surfaces being 0 greater area than the inner beveled surfaces whereby a pressure applied to the operatively positioned edges will tend to move said edges toward the axis of the stock and means for preventing a longitudinal movement of the its within the slots.-

9.- A drill comprising a stock having arcuate, oppositely inclined slots on opposite sides of the axis of said stock; areuate bits removably mounted 'within the slots and having double-beveled cutting edges, the.

outer beveled surfaces being of greater area than the inner beveled surfaces whereby a edges, the i pressure applied to the operatively positioned edges will tend to move said edges toward the axis of the stock and a ring rotatably mounted upon the stock to prevent a longitudinal movement of the bits within the" slots, said ring being provided with .a gap slightly narrower than bits. g

10. A drill comprising a stock having arcu'ate, oppositely 'nclined slots on opposite the width of the sides of the axis of said stock arcuate bits removably mounted within the -slots and having double-beveled cutting 'edges, the outer beveled surfaces being of greater area than the inner beveled surfaces whereby a pressure applied to the operatively positioned edges will tend to move said edges tof Ward the axis of the stock; a ring rotatably mounted upon the stock to prevent a lon 1- tudinal movement of the bits within t e slots, said ring being provided-with a gap slightly narrower than the width of the bits; and the ends of the ring being bevel-edged in order to removal of the bits.

11. A drill comprising a stock having arcuate, oppositely inclined slots on opposite sides of the axis of said stock; arcuate bits removably mounted within the; slots and having) double-beveled cutting edges, the outer eveled surfaces being of greater area than the inner beveled surfaces, pressure applied to the operatively positioned edges will tend to move said edges toward the axis of the stock; and a plurality of rings rotatably mounted upon the stock to prevent a longitudinal movement of the facilitate the insertion and the.

whereby a ward the axis of the stock;

insane bits within the slots, each of the rings having a gap therein slightly narrower than the width of the bits. 12. A drill comprising a stock having arcuate, oppositely inclined slots on opposite sides of the axis of said stock; ,arcuate bits removably mounted within the slots and havingdoublebeveled cutting edges, the outer beveled surfaces being of greater-area than the inner beveled surfaces, whereby a pressure applied to the operatively positioned edges will tend to move said edges toa plurality of rings rotatably mounted upon the stock to prevent a longitudinal movement of the bits within the slots, each of the rings having a gap therein slightly narrower than the width of the bits; and the ends of each ring a mounted within the slots i been shortened; a plurality of being beveled-edged in order to facilitate the insertion and the removal of the bits.

13. A drill comprising a stock having slots therein; double-edged bits removably mounted within the slots and having one cutting edge longer than the other edge thereof whereby said'bits may be reversed and the shorter edges used without binding when the longer edges have been shortened; and a ring rotatably mounted upon the stock and arranged to retain the bits therein, said run thai the width of the bits.v

14. A drill comprising a stock having slots therein; double-edged bits removably mounted within the slots and having one cutting edge longer than the other cutting edge thereof whereby said'bits may be reversed and the shorter cutting edges used without binding when the longer edges have been shortened; a ring rotatably mounted upon the stock and arranged to retain the bits therein,said ring having a gap therein of lesser width than the width of the'bits; and the ends of the ring being bevel-edged in order to facilitate the insertion and the removal of the bits.

15. A drill comprising a stock having slots therein; double-edged bits removably and having one cutting edge longer than the other cutting edge thereof whereby said bits may be reversed and the shorter cutting edges used without binding when the longer edges have been shortened; and a plurality of rings rotatably mounted upon the stock to retain the bits within the stock, each of the rings having a gap therein of lesser width than the thickness of the bits.

16. A drill comprising a stock having slots therein; double-edged bits removably mounted within the slots and having one cutting edge longer than the other cutting edge thereof whereby said bits may be reversed and the shorter cutting edges used without binding when the longer edges have rings rotahaving beveled having a gap therein of lesser width tably mounted upon the stock to retain the bits within the stock, each of therings having .a gap therein of lesser width than the thickness ofthe bits; and the ends of each ring being bevel-edged in order to facilitate t e insertion and the removal of the bits.

' 17. A drill comprising a stock having slots therein oppositely inclined on opposite sides of the axis of said stock; doubleedged bits removably mounted within the slots and having beveled cutting edges, the outer beveled surfaces being of greater area than the inner beveled surfaces, whereby "a pressure applied to the operatively positioned cutting edges will engage said outer beveled surfaces and thereby tend to move said cutting edges toward the axis of the 18. A drill comprising a stock having slots therein oppositely inclined on opposite sides of the axis of said stock; double-edged bits removably mounted within the slots and cutting edges, the, other beveled surfaces being of greater area than the inner beveled surfaces whereby a pressure applied to the operatively pesitioned cuttingedges will engage said outer beveled surfaces and thereb tend to move said cutting edges toward th e axis of the stock, said bits being also provided in their ends with recesses; means for and a ring rotatably mounted upon the stock and arranged to engage the recesses to retain the bits within the slots, said rin having a gap engaging the recesses t0 retain the bits within the slots ,10(]

therein of lesser width thant 1e thickness of I the bits.

19. A slots therein oppositely inclined on opposite sides of the axis of said stock; double-edged bits removably mountedwithin the slots and having beveled cutting edges, the outer beveled surfaces being of greater area than the inner beveled surfaces, whereby a pressure applied to the operatively positioned cutting edges will engage said outer beveled surfaces and thereby tend to move said cutting edges toward the axis ofthe stock, said bits being also provided in their ends with recesses; means for engaging the recesses-t0 retain the bits within the slots; a ring rotatably mounted upon the stock and arranged to engage the recesses to retain the bits within the slots, said ring having a gap therein of lesser width than the thickness of the bits; and the ends of the ring being beveledged in order to facilitate the insertion and the removal of the bits.

slots therein oppositely inclined on opposite drill comprising a stock having sides of the aXis of said stock; double-edged bits removably mounted within the slots and ' applied to the operatively positioned cutbits being slots therein oppositely innerbeveled surfaces,

applied to the operatively positioned cutting will engage said outerbeveled ting edges to move said outsurfaces and thereby tend ting edges toward the axis of the stock, said also provided in their ends with recesses; and a plurality of rings rotatably mounted upon the stock and arranged to enage'the recesses for retaining the bits withinthe slots, each of the rings having a gap therein of lesser width than the thickness of the bits. I

21. A drill comprising a stock having inclined on opposite sides of the axis of said stock; double-edged bits removably mounted within the slots and having beveled cutting edges, the outer beveled surfaces being of greater area than the whereby a pressure edges will engage said outer beveled surfaces and thereby tend to move" said cutting edges toward the axis of the stock, said bits being also provided in their ends with recesses; a

pluralityof rings rotatably mounted upon the stock and arranged to on age the recesses for retaining the bits wit in each of the vrings havin a gapv therein of lesser width than the thiclmessoi the bits; and the ends of each ring being bevel-ed in order to facilitate the insertion and the removal of the bits. 4

22. The combination with a drill of arouate, double-edged bits detachably connected to and oppositely inclined on opposite sides of the axisofsaid ate to and oppositely inclined drill, each bit having one cutting edge of greater length than the other edge whereby said bits may be reversed and the shorter cutting edges used without binding when the longer cutting edges have become shorter than the originally shorter cut, ting edges.

23. The combination with a drill oi arouate, double-edged bits detachably connected to and oppositely inclined on opposite sides of the axis of said drill, each bit having one cutting edge of greater lengththan the other edge whereby said bits may be reversed and the shorter cutting edges used without binding when the longer cutting edges have become shorter than the origina ly shorter cutting edge; and means for detachably connecting the bits to the drill.

24:. The combination with a drill of aroudouble-edged bits detachably connected of the a-xis of said drill, eachbit having one cutting edge of greater length than the other 1. inn; 7 a ..i

versed and the shorter the slots,

ged'

on opposite sides edge whereby said bits may be reversed and come shorter than the originally shorter cutting edges; and. a ring rotatably mounted upon the drill, said ring having a gap therein of lesser width than the thickness of the its. a

25. The combination with aidrill of arouate, double-edged bits detachably connected to and oppositely nclined on opposite sides of the axis of said drill, each bit having one cutting edge of greater length than the other edge whereby said bits may be recutting edges used without binding when edges have become shorter than the originally shorter cutting edges; a ring rotatably mounted upon the drill, said ring having a gaptherein of lesser width than the thickness of the bits; and the ends of the ring the longer cutting being bevel-edged in order to facilitate the insertion and the removal of the bits.

26. The combination with a drill of arouate, double-edged bits detachably connected to and oppositely inclined on opposite sides of the axis of said'drill, each bit having one cutting edge of greater length than the other edge wherebysaid bits may be reversed and the shorter cutting edges used without bind- 1 ing when the longer cutting edges have bee come shorter than the originally shorter cutting edge; means for the bits to the drill; and a plurality of rings rotatably mounted upon the drill, to engage and detachably connect the bits each of the rings having a gap therein of lesser width than the thicknessof the bits.

27. The combination with a drill of arouate, double-edged bits detachably connected to and, oppositely inclined on opposite sides of the axis of said drill, each bit having one cutting edge of greater length than the other edge whereby said bits may be reversed and the shorter cutting edges used without binddetachably connecting to the drill,

ing when the longer cutting edges have become shorter than the originally shorter cut- W tanner BERNAY. 

